Safety Practices & Troubleshooting Techniques Flashcards

An irrigation system has zones that randomly turn on and off at unpredictable times. The controller does not show these zones as active. What is the most likely cause?

Answer: A short circuit in the field wiring is allowing stray current to activate solenoids when other zones run or when external electrical interference occurs

Random, phantom zone activation not shown on the controller indicates that stray current is reaching solenoids through damaged field wiring. Short circuits between zone wires, damaged insulation, or water-saturated splice connections can leak enough current to partially or fully open solenoid valves.

When working near overhead power lines during irrigation installation, OSHA requires maintaining a minimum clearance distance of:

Answer: 10 feet for lines under 50kV, with greater distances for higher voltages

OSHA requires a minimum 10-foot clearance from overhead power lines carrying up to 50kV. Higher voltage lines require greater distances. This applies to all equipment, materials, and workers — including raised pipe, trencher arms, and hand tools.

A zone runs longer than the programmed run time and won't shut off from the controller. The technician verifies the controller is commanding the zone to stop. What should be checked?

Answer: The zone valve solenoid, diaphragm, and controller triac — the valve may be stuck open mechanically, or the triac may have shorted in the 'on' position

A zone that won't stop has either a mechanical valve problem (debris holding the diaphragm open, torn diaphragm, stuck bleed screw) or an electrical problem (the controller's triac has shorted in the closed/'on' state, continuously sending 24 VAC to the solenoid).

Proper lifting technique when moving heavy irrigation materials (boxes of pipe, bags of gravel) requires:

Answer: Bending at the knees, keeping the load close to the body, maintaining a straight back, and lifting with the legs

Proper lifting technique protects the spine: bend at the knees (not the waist), grip the load firmly and hold it close to the body, maintain a neutral spine, and use the powerful leg muscles to stand. Never twist while lifting — move your feet to turn.

During troubleshooting, a technician identifies that a zone has low flow but the valve is fully open and the wiring is correct. The next step should be to check for:

Answer: A partially closed upstream isolation valve, a clogged filter or strainer, a restricted backflow preventer, or a crushed/kinked pipe in the supply line

When the zone valve is confirmed fully open but flow is restricted, the obstruction is upstream of the valve. Common causes include a partially closed ball valve, a clogged filter screen, sediment in the backflow preventer, or a crushed pipe section reducing the water supply to that zone.

What is the purpose of maintaining a daily job log or service report for irrigation work?

Answer: To document work performed, conditions found, materials used, time spent, and recommendations — providing legal protection, customer communication, and business records

Daily documentation serves multiple purposes: legal protection in case of disputes or liability claims, accurate billing records, customer communication about system condition, tracking of recurring problems, warranty documentation, and business performance analysis.